Improvement in shaft-furnaces for roasting ores



'1'.MCGLEW.

Shaft-Furnaces for Roasiing Dres.

.Patenredjuly15,1873.

' wmwfws 1 (2%, y m

AM, mami/momma ca Musso/enfle mqcassl) UNITED STATES THOMAS MGGLEW, OF AUSTIN, NEVADA.

IMPROVEMENT IN SHAFT-FURNACES FORROASTING ORES.

Specification forming part of Letters Patent No. 140,837, dated July 15, 1873; application filed April 9, 1873.

To all whom it may concern:

Be it known that I, Tuoi/[As MCGLEW, of Austin, Lander county, State of Nevada, have invented an Improved Chloridizing-Furnace; and I do hereby declare the following description and accompanying drawings are sufficient to enable any person skilled in the art or science to which it most nearly appertains to make and use my said invention or improvement without further invention or experiment. i

My invention relates to an improved furnace for roasting and chloridizing ores which have been previously pulverized and mixed with a quantity of salt, and is what I call the Eagle Improved Chloridizin g Furnace. My improvements consist in combining in aroasting and chloridizing furnace, the principles of the stack or upright furnace, and of the reverberatory furnace insuch a manner that the ore infalling through the upright portion of the furnace will meet, or rather come in contact with, the heat and blast from one or more blast furnaces, situated at different points along its descent, and will finally fall upon a hearth over which the combined heat and blast fromall of the furnaces pass to the chimney or draft-flue.

In order to more fully illustrate and explain my invention, reference is had to the accompanying drawings forming a part of this specilication, in Which- Figure 1 is a side sectional elevation. Fig. 2 is a side elevation.

A represents the main body of the furnace which will be built to a considerable height, as desired. B is the reverberatory hearth, and C the chimney or draft-flue. D E F are dre-places, ranged at different heights in the body of the furnace A. Upon the top ofthe furnace A is the feed-hopper G, the bottom of which is connected by an inclined spout or chute, O, with the inclined passage H in the front of the furnace A. Each of the fire-places D E F communicates with the inclined pas` 0r valve, m, is connected with each of the pipes j k Z, by which the blast of air from the blower into either or all ofthe fire-places can be regulated.

'lhe ore to be roasted and chloridized having been properly pulver-ized and mixed with salt, is placed in the hopper G, from which it is fed into the inclinedy chute O by a revolving iuted roller or cylinder, p, which is rotated at the desired speed by a belt connecA tion with the power which drives the blower. The chute O conveys the ore and salt into the inclined passage H, where it comes in contact with the blast from the upper fire-place D,which separates the particles and subjects them to the action of the heat; thence it passes downward encountering the blast from the fire-place E, and an increased degree of heat; thence downward past the blast from the hre-place F, and finally drops upon the hearth O Where it remains subjected' to the combined lheat from all three of the hre-places until it has been thoroughly roasted, and is ready to be, drawn forcooling. The roasted ore is drawn Y from the hearth through the side door S.

By this arrangement the ore can be completely and thoroughly roasted and chloridized. As many fire-places can beused at. different altitudes as may be required to complete the process.

I am aware that James D. Whelpley and Jacob J. Storer, in their patents of January 12, 1864, No. 41,250, and of November 13, 1866, No. 59,696, reissued numbers 4,897 and 4,898, used blowers to increase the draft through a vertical or nearly vertical chimney with a fireplace on each side of the chimney near its top 5 but these parties do not apply a blast directly to the lire as I do, nor do they have a succession of blasts arranged on different horizontal planes. I am also aware of the patent to Chas.

Stetefeldt, No. 72,931, December 3l, 1867, re

nace, and heated by fire-places at or near the top.

I disclaim Whatever is shown in these several patents, my improvements consisting in combining` the principles of the shaft-furnace and reverberatory furnace in such a manner that the ore in iine powder falls through the upright portion of the furnace, comes in contact with the blast at different points, and finally falls upon a hearth, over which the ccmbined heat from all the blasts will pass. My improvement consists in making a furnace that differs from those heretofore used in this method of chloridizing, in placing a series of fire-places with blast apparatus at different heights along the descending shaft and casting the ore upon the hearth Where it is subjected to the combined action of the several blasts.

I do not claim the process of forcing'or dropping the ore in a fine powder through a shaft, nue, or furnace, and subjecting it to heated gases or the products of combustion; nor do I claim a furnace for roasting ores composed of a shaft or chamber, through which the ore in tine powder may be blown or fall, suchk being described and claimed in the patents to Whelpley and Storer, above referred to; nor the process of chloridizing silver ore by dropping a mixture of pulverized ore and salt through a vertical or nearly vertical shaft with the products of combustion, such .being claimed in the patent to Eugene N. Riotti, March 28, 1871.

Having thus described my improved roasting and chloridizing furnace, what I claim, and desire to secure by Letters Patent, is

In an ore roasting and chloridizing furnace, the nre-places D E Fon different horizontal planes, and with the draft arranged, as shown, so that it will strike and scatter the falling ore, in combination with the inclined passage- Wa5 H, blower J, hearth B, and chimney C, all constructed and arranged substantially as and for the purpose set forth.

In Witness whereof I hereunto set my hand and seal.

THOMAS MCGLEW. [n si] Witnesses:

BENJAMIN B. STANSBURY, MILTON R. BOWMAN, WILLIAM K. LOGAN. 

